Z840 Performance

[Lars_Poster]

I picked up a used Z840 recently with 128 Gb of DDR4 (mixed 2133 and 2400 MHz) and two E5-2673 V4s in it. 

I need this for long (weeks) of "embarrassingly parallel" calculations. I made no attempt at any kind of optimization although I did set the bios and power settings to the recommended setting described on this website.

I ran it through a few benchmarks and was pleasantly surprised! For 300 Euros, a 10 year old set up could hold its own (in multi core work) against the more modern systems I had been considering (like low end Threadrippers) that still cost nearly twice as much second hand!

There may be something wrong with the temperature setting as even stressing the cpus for hours...they never gets above 65 C.

There was a thread on here about turbo problems with these CPUs and that may be true.....both CPUs never get above 2.6 GHz on multi cores stressing (expected) but no core ever gets above that on using single core stressing (they theoretically could reach 3.5 Ghz). This may be my fault as I have the latest bios (needed it for the v4's) and it seems that has caused issues for some.

Either way, I am very happy - these two CPUs seem very good value for the tasks I bought it for and compare well with modern CPUs in those tasks.

P

[SDH]

Use this forum's search feature top left area and search for Turbo Boost. You'll find quite a few prior posts to read up on, and also search via google for HP Turbo Boost. Google finds things that our search feature fails to find (even posts in this forum itself).

Here's the basics:

1. You have to have processor(s) that can do that.

2. It takes more energy to run faster... and it makes sense that by mandate or by good intentions the HP Factory Default BIOS settings are energy saving. Thus, during your reading you'll see that a number of necessary BIOS changes from defaults have to do with turning off certain energy saving features. You sure you need to run at full speed all of the time?

3. Latest BIOS and OS is generally a good idea. Those include bug fixes and microcode updates.

4. There are even system settings that come into play. For example, in Control Panel under the Power Options app you need to have High Performance selected.

[DGroves]

the HP turbo bios setting should in general not be changed from the default setting, doing so will cause issues with some other bios settings

all that is usually required is set bios to factory defaults and disable boot from lan and disable the onboard LSI sas/sata bios, the boot drive should be on the 2 grey/blue sata 3 6GBps ports and other sata drives connected to the 5 intel "SCU" ports located next to the two sata 6 ports

the LSI SAS/SATA located on the edge of the motherboard can still be accessed by the os when the LSI boot rom is disabled only the ability to boot from these ports is disabled

if using windows, simply set the default power plan from default to high performanced (click on the advanced link)

these settings may be helpful if the HP defaults fail to give good results

Z840 dual cpu Hyper-Threading enabled Settings:
Please Note: CPU Hyper-threading should be enabled. It may be disabled by default

Z840 Required system BIOS settings:

1. Verify CPU Processors are set to Hyper-Threading
2. Set Memory NUMA – Disable
Z840 Optional system BIOS settings**
** Only required if the User is experiencing recognition, operational or audio “popping” when using a USB
audio I/O device (such as an Mbox or 3rd party USB audio device). These settings will resolve any of these
issues which might be experienced with USB audio I/O devices. if not using these devices leave setting at defaults

1. Set Runtime Power Management - Disable
2. Set Idle Power Savings - Normal
3. Set Intel Turbo Mode – Disable

Set Z840 Required system BIOS settings:
- During boot up press F10 at the HP splash screen to invoke Set Up.
- Select the Advanced tab
- Select Performance Options
- Verify Intel Hyper-Threading setting is Enable
 If Hyper-Threading is set for Disable then it must be changed to Enable
- Return to the Main screen
- Select Advanced Tab
- Select Performance Options
- Select Non-Uniform Memory Access (NUMA)
- Default setting is Enable
 Change this setting from Enable to Disable

 run a memory benchmark or test your program to see which setting is faster

 usually the default setting is preferred but specific software or available ram

 may have a impact on this setting
- Return to the Main screen
- Select “Save Changes and Exit”
- When prompted to “Save Changes?” , select “Yes”
- System will reboot

Set Z840 Optional system BIOS settings:

**Only required if connecting USB audio I/O devices

and experiencing any of the issues described above..
- Select Advanced Power Options
- Select Runtime Power Management
- Default setting is Enable
 Change this setting from Enable to Disable
- Select Idle Power Savings
- Default setting is Extended
 Change this setting from Extended to Normal
- Return to the Main screen
- Select the Power tab
- Select Hardware Power Management
- Select Turbo Mode (This setting might not appear once the Runtime Power Management setting has
   been disabled. This is o.k. and means Turbo Mode has been disabled).
- Default setting is Enable
 Change this setting from Enable to Disable
- Select “Save Changes and Exit”
- When prompted to “Save Changes?” , select “Yes”
- System will reboot

[SDH]

We forgot to give you an added significant tip:

You have a weak link in your chain. With any 2133 memory stick in place your other memory sticks all will downshift in speed to 2133. And, your processors both will also downshift to that too. The Intel ARK web site give you processor's max speed as:

DDR4 1600/1866/2133/2400

With a tuned workstation you can perceive that slowdown so I'd recommend getting rid of any 2133 sticks. It is best to match the 2400 speed sticks you already have. eBay can help you with that... recycled RAM for the ZX40 workstations has come down in price quite a bit.